Avid BB7 MTB S Disc Front or Rear Brake 180 Rotor:All calipers have 74mm mounting-bolt spacing and include adaptors for 51mm International Standard brake mounts⋅ For use with with long cable-pull levers⋅ Pad retraction and spring tension are adjustable⋅ Includes G2 Clean Sweep rotor⋅ Due to the shape of the brake pad installation tabs⋅ this model is not compatible with Centerlock or HSX rotors